The Prank that Started it All
by NatashaAndTheBoys
Summary: When Darcy decides to prank Steve in retaliation for interrupting her plotting with Tony, she runs into an unexpected someone when leaving his room. Has she found the ultimate partner in crime?
1. Chapter 1

**A/N: this is my first story for this fandom so enjoy!**

Darcy crept down the hallway, cautiously peeking around the corner before sprinting the last few metres to Steve's bedroom. She eased the door open, silently thanking that it didn't creak. She had big plans for this morning and a noisy door would put a stop to all of them. Looking around one more time, Darcy slipped into the room, dropping the bag from her shoulder onto the floor with a soft whump.

She nearly cackled at what she saw as she looked around the room: Tony had obviously had a hand in the decorating. War propaganda from the 40's decorated the walls, all heavily featuring Steve in his star-spangled uniform.

But where to start? Darcy picked up the bag she had packed, opening it to reveal the results of her shopping trip the previous afternoon. Piece after piece of lingerie lay there, just waiting to be hidden to embarrass their resident super soldier.

That will teach him not to stop Tony and my plotting! Not that he'll know it was me. He'll probably think it was Tony. Nah, way too subtle. Loki? Maybe.

The moody demigod had moved into the tower as part of his punishment from Odin and had yet to talk to anyone apart from Thor, as far as Darcy knew.

"Focus Darcy! You have a limited time frame here." She got to work, carefully hiding the undergarments around Steve's room. Ta-da! Only one more to go. She looked around, then smirked, moving forwards to tuck a particularly lacy pair of panties behind Steve's shield.

Man, he's going to be so embarrassed, she thought.

Darcy snickered as she headed for the door.

She was nearly skipping by the time she reached the threshold, taking one look back at her work before wrenching the door open and – smack!

"What the heck!" she exclaimed as she looked up at the body she had ran into. Not good Darcy, not good, she chastised herself. Standing in front of her was Loki, the God of Mischief himself, and he didn't look impressed.

"What are you doing, mortal?" he sneered. Naturally, Darcy's brain-mouth filter was broken again and so she blurted out "It's Darcy, actually."

"What?"

"Darcy. My name. Not mortal." Not cool Darcy, not cool.

He looked nonplussed. "Darcy, then. You still haven't answered my question… what are you doing?"

Make up something smooth. Believable. Fool the God of Lies. No problem.

"Ahhh… I might have been hiding panties around his room to embarrass him when he gets back?" She clamped both hands over her mouth. See Darcy? This is what happens when you open your mouth! Idiot! She berated herself.

Darcy looked up to see what might have been a smirk playing along the edges of Loki's mouth.

"Well," he drawled, "I'm sure there is a little something I can add to that. All in the name of educating our good Captain, of course."

He frowned for a moment, staring at the door before relaxing his face and smirking again.

Darcy couldn't help herself. "What did you do?"

"Hmm? Oh. I added a little something extra to your idea."

"That's all you'll say? Come on, I set the thing up anyway. If you're going to step in and interfere, at least tell me what you did." she snapped.

Loki raised an eyebrow at her. "You are a very strange mortal. First you respond to my questions by telling me about your plans to embarrass the Captain and then have the audacity to question me about what I am doing with such impertinence?"

"Well, yes."

"I find it rather endearing."

"…Thanks?" she tried.

"You're most welcome. In answer to your earlier question, Darcy, I simply… added to the amount of clothing you placed in the Captain's wardrobe." Anticipating her question, he smirked again. "To put it simply, he may be getting an interesting surprise when he opens his cupboard next. Which I anticipate will be in about an hour when he returns from his run."

With that, Loki turned away and disappeared.

Darcy found herself staring back with her mouth hanging open. Close the mouth Darcy, you'll catch flies, she told herself. But damn! She had thought she was busted for sure, but now… was it possible she had an ally for these pranks? Steve wasn't the only one on her list.

An hour later

Darcy sat in the kitchen, idly standing in front of the coffee machine as she strained to listen down the hall. Steve had just entered his bedroom and she wanted to hear his reaction to her prank.

Natasha was sitting on the couch in the other end of the communal area, elbow resting on Clint's head as he snored next to her, slouched down. Bruce and Tony were talking about some science thing using words with too many syllables for Darcy to understand.

Interestingly, Loki was also in the kitchen area, awkwardly perched at the counter. It was the first any of them had seen of him for days. Except me, Darcy thought. I saw him not too long ago at all.

She was still standing in front of the coffee machine when Stark walked up to her.

"Hey Lewis! Are you going to make coffee or just stand there ogling my machine? I know, it's fantastic, I designed it, but– " he was cut off by Loki.

"Shhhhh!"

Everyone went silent just in time to hear a wail coming from Steve's room.

"Arghhhh!" Darcy smirked.

There was a bang from the hallway and a few seconds later Steve came running into the common area, wearing only a towel. Usually Darcy would have appreciated the exposed muscles – the man was a super soldier all right – but today she was too busy sniggering at the lacy bra hanging off Steve's shoulder and his look of disarray.

Stark still stood in front of the coffee machine, eyes boggling. "What happened to you, Spangles?" he asked.

Steve flushed red. "I-I-I don't know!" he exclaimed. "I opened my wardrobe and-and- there were ladies- clothes everywhere!"

Darcy was struggling to keep the laughter off her face as she watched the super soldier squirm.

As Steve continued to explain, Darcy glanced around the room at the others. Natasha had a smirk plastered on her face as she pretended to continue reading her magazine on the couch. Clint was still asleep and Bruce was looking slightly bewildered.

Darcy managed to keep a straight face right up until she caught Loki's eye: he had a full-blown smile on his face and looked genuinely happy. Like she might have imagined he would have looked like before turning evil and trying to destroy the world.

She cracked up laughing, ignoring the questioning looks turned her way. Not only had she pranked Steve and embarrassed him so very much more than she thought she would, she had brought the God of Mischief in on it too!

The future looked bright indeed.

**A/N: So I hope you liked it! I'm thinking of developing this into a series of one-shots with Darcy and Loki pranking the rest of the Avengers so tell me what you think!**


	2. Chapter 2

Darcy sighed. She'd been walking around for a good half an hour looking for Loki and the coffee she'd been holding in her right hand was nearly cold. It was probably a stupid idea anyway. Did gods even drink coffee?

She rotated the cup to check the label: iced caramel macchiato from the Starbucks around the corner. Tony would be indignant that she wasn't making use of his coffee machines but sometimes a girl just wants what she wants, you know? And having to argue with the machine to get anything like what she asked for to drink wasn't it.

Darcy threw the empty coffee cup in her other hand into a nearby bin – score! – and continued down the hall. Surely she had to find him soon – she'd looked nearly everywhere in the Tower! She paused. Now, where would she hide if she was a recalcitrant, moody demigod? Aha!

Darcy pivoted on her heel and headed back the say she'd come. She knew just where to look.

The doors opened before her and Darcy stepped onto the roof. "Nice place you've got here."

Loki barely responded, shifting aside from where he sat on the edge of the roof, looking over the city.

"Pretty, isn't it?" He didn't reply. Darcy sighed.

"Look, dude- Loki. Can I sit?" She took his silence for acquiescence. "Are you alright?"

Still no reply.

Alright, then. "So let's just assume that's a no, you're not alright and also a no, you don't want to talk about it. I want to continue our pranks. Like it doesn't have to be our pranks, but given as you helped me with the first one and it might be fun and you know, magic, and that's got to help with pranks and oh god I bet you played so many pranks on Thor –"

Loki interrupted her. "You are a very hard mortal to understand, sometimes."

"So that's a yes?"

"I suppose."

Darcy beamed. "So, who should we prank next? I was thinking Bruce, but then that's not cool because he has that unfortunate tendency to, you know – "

" –I am aware."

"Oh. Right. Anyway, then I thought we could prank Barton because he's been being a little shit and shooting Nerf arrows out of the vents, but then I thought he might take it the wrong way if you're involved."

Not cool, Darcy! Remind the man that people still hate him for what he's done. Crap.

"Ummm…"

"Why not prank the Lady Natasha?" Loki interrupted.

Darcy snorted. "Are you serious? Do you want to die by ice-cold scary Russian assassin?"

Loki inclined his head. "It is a fair point you raise. So, Stark then. We can prank my brother at another time."

Darcy squealed. "Yay! What should we do?" She waited to see what he would come up with. This better be good, she thought. I didn't go to all this effort to get your help for nothing. Which reminded her – coffee!

She thrust out the hand that still held the cold coffee cup. "Here. I, umm, brought you coffee. It's probably cold. And it's got caramel in it, so I don't know if you like that, but –"

Loki took the cup from her outstretched hand and smiled: a proper smile like the one they'd shared after their first prank. "Thankyou, Darcy."

It's probably the first thing anyone's done for him that's nice since he got here, she realised. "No problem."

Silence.

"So what are we going to do? I didn't go to the trouble of tracking you down – hard by the way, I mean seriously? The roof? – to sit here and contemplate the view. What should we do?"

Loki smirked. "I believe I have an idea. What do you know about the robots Dummy, You and Butterfingers?"

Darcy was nearly skipping as she headed down to Tony's lab. "Can you hear me?" she asked. To thin air, she reminded herself.

"Yes, I can hear you." Loki's voice replied patiently. "Just like I could the other thirteen times."

But this was so cool! Darcy grinned.

As the elevator arrived, Darcy peered around the corner. Lab – empty. Check. "I'm a genius!" she sang.

"How so?" Loki's voice was clear in her ear even though he was nowhere to be seen.

"I checked Pepper's schedule – no point checking Tony's, really, and she had a lunch scheduled with him. No way he's getting out of that. And he's not here! Woohoo!" Darcy did a little happy dance and heard Loki snigger in her ear. "Don't judge."

She silently – mostly silently – slid open the door to Tony's lab and stepped inside.

"Tell me what I need to move. Seriously, once this starts I don't want to be knocking any dangerous crap over." Loki appeared next to her without a sound and she jumped, knocking a vial off the bench next to her. Loki reached out and snagged it before it hit the ground.

"See! That's exactly what I mean! It's not safe! Also, how did you get here so fast?"

He smirked. "I can teleport to wherever I choose, you know."

"Bet you used that on Thor as kids – but then why let me come down here first?"

"I wanted you to have your moment of greatness."

Well, fine then. She humphed.

Loki crouched down over Dummy, leaning forwards. "How do I turn it on?"

Dummy jerked upright and smacked Loki on the face with his claw-arm-thing. Darcy sniggered. "You have to be nice to him. Dummy?"

The bot rotated to face her. "Is it ok if Loki has a bit of a poke around? We want to play a trick on Tony." Dummy turned to face Loki.

"How did you do that?" he asked incredulously.

She smirked. "Dummy and I are great friends. Comes from bringing Stark coffee and dragging him off to bed more times than I can count."

"And why has this task fallen to you?"

"Pepper's away for work a lot. That's why she wants to go for lunch with Tony while she's here."

He nodded. "Ah. Well, now that I know what to do, I believe you're on distraction duty Miss Lewis."

She nodded and marched out the door.

"Ah no, I haven't seen Loki lately. Why?" Darcy stood in front of a pacing Tony Stark.

"I, ah, – Pepper had to cancel and so I need him to run some tests in the lab. No biggie, he just said he'd be happy to help." The genius paused. "I might run down there now and check, actually. Thanks!"

With that, he sprinted back towards the lab. Crap.

Darcy stepped to the side and whispered to the empty room. "Loki! Err, I really hope you can hear me now cause Stark's headed down to the lab and you probably don't want to be there when he arrives."

No reply.

Darcy took off down the hall. She needed to stop Stark before he reached the lab and if all else failed, she wanted to watch.

As she sprinted through the common floor, the other Avengers looked up. "Are you alright, Darcy?" Steve asked worriedly. She flashed him a thumbs up but didn't stop. She knew they'd follow.

Eventually Darcy stopped, panting for breath, at the end of the corridor to Tony's lab. "I really hope you got out, Loki," she hissed under her breath. Steve, Natasha and Thor arrived behind her, looking down the hall.

"What is happening that had you so flustered, Lady Darcy?" Thor boomed. She frantically shushed him as she crept down towards the lab.

Loki popped into existence next to Darcy, making her jump. "Dude! Stop doing that!" she whisper-shouted. They all continued down the hall, Steve and Thor looking confused and Natasha with a little smirk on her face.

Tony entered the lab and looked around. "Loki? Nope, not here." He turned and headed for the door, catching sight of the group just as the doors closed. "What the –"

Then all hell broke loose.

Dummy shot out from behind a bench holding his favourite fire extinguisher and sprayed Tony with it. You and Butterfingers entered the fray, one holding a mostly full smoothie maker and the other – was that Steve's shield?

Darcy sniggered, turning into full-blown laughter as Tony tripped and fell on the floor, Dummy moving closer to continue spraying him. Tony's mournful shrieks of "I've been betrayed! Betrayyyedddd I tell you!" didn't help either.

Natasha and Steve were cracking up behind her, Thor looked confused, and Loki had another smirk playing around his face. But wait – where was Clint?

Darcy heard a thump from the lab and swung around to see Clint, who had apparently just fallen from one of the vents, stop his hysterical laughing as Dummy turned and started to spray him too.

Her sides hurt from laughing, and as she looked to her side she saw that Loki was laughing too. Two for the price of one! She turned back to the lab and giggled at the mess inside. Oh, this was fun.

Darcy headed back into her room after a long, relaxing shower, only to see a scrawled note lying on her pillow – just under the ventilation shaft to her room.

She picked it up and grinned as she read:

"This means war. Love, Tony and Clint".

Oh, it was on.


	3. Chapter 3

**A/N: So the story continues!**

"I've got it!" Tony dashed into the room and grabbed Clint, dragging him out the door and down to Tony's lab.

"Got what?" Clint had been enjoying a lovely nap until Tony came barging in on him.

"I know who we should prank! And what to do!" Tony sang, before turning to face Clint's unimpressed expression. Tony frowned. "For our prank war? Do you not remember?!"

Clint sighed and cast his eyes around for the nearest chair. For some reason, he knew this was going to take a while. "Have at it, Stark."

"We prank Natasha."

"No."

"By adding detergent to her showerhead so her entire floor gets flooded with bubbles."

"No."

"Bright pink bubbles that dye everything they touch?"

"…No."

"But Clint! Why not?" Tony whined.

Clint sighed. Why he had to deal with the immature genius was beyond him. "Because, if we prank Natasha, we'll die. Simple."

"But you're the only one who can help do it! You're the only one who knows her well enough to get past the booby traps in her room!" Tony beseeched. "I'll design you a new type of arrow."

"…Fine."

Darcy cackled. "They're going to try and prank Natasha?" She clamped her hands over her mouth.

"They can't hear us too, can they?" she whispered.

Loki smirked. "No, the spell is strictly one-sided. I must say, I find the idea of Stark trying to prank the Lady Natasha very amusing."

"Well, we'll have to out-prank them then." Darcy thought for a moment, before a look of bliss came over her face. "I think it's time we pranked your brother."

Loki's face broke out in a very real smile. "Excellent idea. What would you suggest?"

"Seeing as he isn't overly familiar with Earth customs yet, we could convince him that there's some tradition to strip down in Times Square to show his manliness?"

Loki shuddered. 'No thank you. That is not a sight I ever need to see again in my life."

"Well, then – again? Tell me. Now." Darcy demanded.

"It's a long story, but it ended with Thor having to dress in a bride's costume in order to regain Mjolnir after it had been stolen. Needless to say, he was eager to get out of the dress."

Darcy sniggered. "That's something you will be explaining later in great length."

"What will he explain?" Clint's head popped out of a vent over their heads. Darcy jumped.

"Goddammit Clint! Don't do that to me!" she paused. "What are you doing here, anyway? You're on the other team!"

Clint dropped from the vent and plonked down on the couch between them, Loki subtly shifting away. "Tony wants to prank Nat."

"We heard."

"How? Anyway, I can't be involved in the prank or she'll kill me but I already told Tony I would and he's going to design me a new arrow if I do." Clint sighed. "So I came here to join up with you two, I guess."

Loki sat contemplatively for a moment. "I have an idea."

Clint perked up. "You do?"

"If the prank doesn't work, then the Lady Natasha will not harm you, correct?"

"I guess."

"So all you need to do is ensure that Tony puts the prank in the wrong shower and then you should be fine." Loki smirked, looking pleased with himself. Then he frowned. "Do you have any ideas for how we should prank Thor?"

Clint paused for a moment. Finally he had a solution that wouldn't involve Natasha's eternal hatred! He shivered, remembering the last time he'd screwed up. He'd been sleeping on the couch for weeks.

"Clint?" Darcy prompted. "We were thinking – well I was thinking – about doing something about Thor not knowing our customs or traditions."

He looked up. "Oh, sorry. Yeah, that sounds good." He considered for a moment. "Why don't you change the settings on his pop-tart maker and coffee machine?" He grinned. "You know how much Thor loves his pop-tarts."

Tony had designed a huge communal living area for the Avengers to share and had populated it with several different coffee machines, one of which was now Thor's. He had also added a pop-tart maker, claiming that "It'll save money in the long run anyway, with the amount Point Break eats." No one was fooled.

"Perfect!" Darcy exclaimed. "I knew they called you Hawkeye for a reason."

Clint slithered through the vents and popped into the kitchen. Darcy squeaked then turned around to glare at him. "Stop doing that!"

He grinned. "I moved the prank for Natasha to Steve's bathroom instead. Had to do it through the vents, so there's no way Tony noticed."

Loki nodded. This so-called 'prank war' was starting to be rather amusing after all, particularly since he was getting to make a fool of his brother. He finished reprogramming the coffee machine and stepped back to admire his handiwork.

"Done!"

Darcy smirked in what he was sure she thought was a threatening manner, but really came across as cute. Did he just describe the mortal as cute?

"Perfect. Now we wait." She said ominously.

Yes, he had just thought of the mortal as cute.

When Thor stumbled into the room an hour later, the whole team was sitting around. Darcy was reading over the Avengers' reports from their latest mission, attacking mistakes with an obnoxiously pink highlighter. Loki sat further down the couch reading _Othello_. Natasha was looking through the fridge for something to eat whilst Clint sat on top of it, talking to her about weapons. And Tony and Bruce were leaning over some schematics on the bench in avid discussion.

Thor made a beeline for the coffee machine, punching the first button he saw.

Nothing happened.

He frowned, shaking off the stupor of sleep for a moment as he hit it again. And again.

Darcy leaned over and tapped Loki on the shoulder as the machine started to shake. "Uh, Loki?" she pointed. "I don't think that's a good sign."

As she said so, the coffee machine exploded, spraying coffee all over Thor, standing in front of it, and Natasha, at the fridge.

Natasha turned slowly to face Thor and growled. "Thor, I swear, if you do this _one more time_" – she flicked a knife from who-knew-where into the wall next to his head – "I will end you."

She stalked out the room gracefully, despite the coffee dripping from her shirt. "Steve, I'm using your shower. It's closest." She left without waiting for a reply. Thor looked ready to pass out from fear. Darcy couldn't blame him.

They'd just started cleaning up the mess from the coffee machine when the team heard a shriek emanating from Steve's bathroom and Clint went white as ash.

"What was that?" Darcy turned to the team and caught sight of Clint's face. "It sounded like Natasha – " Oh no. Darcy felt the sides of her face turn up into a smirk as Clint edged backwards on top of the fridge.

Natasha came stalking into the room, wearing nothing but a bright pink towel and with pink bubbles through her hair and on her shoulders and arms. Clint took one look and bolted for the vents, only to jerk back when a knife appeared right where he was about to put his hand. Seriously, where did she get them from? Natasha grabbed his foot then turned to the rest of the team, impassive. "Get out."

They scuttled from the room, Darcy casting a glance over her shoulder to see Clint shrieking "It was Tony's idea! I tried to stop him!"

Somehow Darcy didn't think that would help.

_Ah, life was sweet_, Darcy thought. No one had seen Clint for the rest of the day. Tony had mysteriously gone missing, only to be found hanging from a harness off the edge of the tower, screaming, and was now ensconced in the lab, frantically trying to find a way to remove the dye that still stained Natasha's skin. Needless to say, she hadn't been happy.

A thought hit Darcy and she sat up, leaning over to poke Loki in the cheek.

"Reckon we could get Natasha on our side to prank the others?" She grinned.

Loki smirked. This prank war was getting better every second.

**A/N: Who should they prank next? Should there be dissent in within the prank team?  
Send me a review and I'll try to add your ideas!**


End file.
